Process of extracting metals from their ores



A. J. MOXHAM.

PROCESS OF EXTRACTING METALS FROM THEIR ORES. APPLICATION FILED NOV 2. 1918. RENEWED DEC. 13.1921.

L 1 Patented June 20, 19

5 III. N

2 SHEETS-SHEET I.

A. J. MOXHAM.

PROCESS OF EXTRACTING METALS FROM THEIR ORES.

APPLICATION FILED NOV-2,19I8. RENEWED DEC. 131192].

Patented June 20, 1922.

lAQILSUn 2 SHEETS-SHEET 2- ARTHUR J. MOXHAM, OF GREAT NECK, NEW YORK.

PROCESS OF EXTJRACTING METALS FROM THEIR ORIES.

Specification of Letters Patent. Pmm r g J 2g) 1922 Application filed November 2, 1918, Serial No. 260,787. Renewed December 13, 1921. Serial No. 522,146.

To all whom it may (BOW-ROTH.

Be it known that I, ARTHUR J. MoxiIA'M, a subject of the King of Great Britain, residing at Great Neck, county of -Nassau, and State of New York, have invented a new and useful Improvement in Processes of Extracting Metals from Their Ores, of which the following is a full, clear, and exact description, reference being had to the accompanying drawings, which form a part of this specification.

The object of my invention is to extract iron from itsores, by means of solvents of iron, in an economical manner. The process comprises the crushing of the ore, dissolving out the metallic constituent from the gangue by means of an acid or other solvent, depositing the pure metal from the solution by electrolysis, and performing the several steps of the process in such manner as to eliminate wastel The several main steps of the process are individually well known, and are not herein claimed as my invention, which comprises the practice of the several steps in definite sequence, and their execution in such manner as will efiect not only a substantially complete winning of all the metal in a pure state, but also the saving of all the materials with which the ore 1s '1 metals from' ore andprepar'ing them for conunercial use; and while, if the ingredients employed were largely or wholly wasted, the expense of the process would be prohibitive, the provisions for saving these ingredients make the process more 8COI10I1'llcal than ordinary commercial processes and result in more valuable products.

\Vhile the practice of the process. is not dependent upon the use of any particular apparatus, the'apparatus disclosed in the accompanying drawings may be used to advantage.

Fig. l is a plan view of the dissolv ng apparatus. Fig. 2 is a deta11 sectional View of oneof the units of the apparatus of F 1g. 1. Fig. 3 is a horizontal section on the hue 33 of Fig. 2. Fig. 4 is an elevation of the electrolytic apparatus.

The ore is crushed to the degree of fineness required to permit the iron oxid to be acted upon by the acid in the course of its subsequent treatment. For ordinary purposes from 20 to mesh is preferred. The clay is washed out by means of a log washer.

The next steps in the process involve the separation of the metal from the ganguc. Mostores are in existence as either sulfides or oxldes of some metal, in conjunction with theaccompanying g'angue, composed almost entirely of silica. I first proceed to dissolve the metal oxide or sulfide in a solvent, pref- 2 and 3. This apparatus comprises a series.

of jigs a, each of which is divided into two )arts by a division wall I), which terminates short of the bottom. On one side of the partition b is an oblong plunger 0 operated by means of eccentrics d (on a common shaft Z) and connecting rods e. The chamber on the other side of partition 5 contains a horizontally disposed screen f arranged above the bottom of the divisionwall. The crushed ore is deposited on the screen.

In the construction of the portions of the' jig above described, material should be used which is unaffected by the usual acids. F or example, the material may be heavy glass plates embedded at the joints in acid-resisting cement, or may be fused silica ware, for instance, that known as vitreosal; or may be acid-resisting bricks, laid up in acid-resisting cement, such as are used in some of the so-called digesters or hydrolyzers. Some of the acid-resisting metals, for example, ferrosilicon, may be used in some cases. The jig should be reinforced by an outside casing properly held together by bolts, the acid-resisting lining preventing the acid from at tacking the casing. i

A hood h is arranged to enclose the otherwise open tops of the two'compartments of the jig, the hood communicating with a pipe 2'. The hood k is provided with a hopper 1O closed and sealed by a cover or door 11.

After the crushed ore is deposited through the hopper 10 on the screen 7, the acid is supplied through the pipe system j. It will, of course, be understood that by suitably located valves, different fluids may be passed through this pipe as to entirely cover the ore. Digestion proceeds for the necessary lengthof time, which time will vary with the acid used, its degree of concentration, the temperature'and other factors. Speaking generally, it will probably be from one to six hours, according to the conditions. After the acid has eifectively operated on the ore, but before the end of this action, the plunger is set in motion from time to time, with the result that the acid is driven between the various pieces of ore, producing such agitation as will facilitate the dissolving process. 7

During the process of digestion and agitation, the lips-g are sealed.

lVhen the iron content of the ore has been dissolved, the resulting iron salt will exist (if hydrochloric acid has been used with limonite ore) as a ferric'chloride. This is run off from the jig through a pipe j (which is commonto the series of jigs) to a storage tank is. The solution should be, or should be made, neutral. J

Water is'now admitted through pipe j to the jig in place of the acid, the openings 9 are unsealed, and the plunger is reciprocated, whereby the gangue remaining'in the jig is pulsated, driven through the openings g, and dropped onto cars m, which are adapted to travel'on a track built along the series'of jigs. Provision is made for draining off the water, as through an outlet n. The cars we carry the gangue to the dumps for the usual disposition.

If it is desired to carry the economy of the acid to an'extreme point, the first Washing with water may be carried to another receiving tank for subsequent treatment for the recovery of any acid washed off the ore, or

for further useby adding concentrated acid "thereto so that the moisture c'arried oil by the gangue is water with only a trace of acid therein.

As much of the'bed of gangue as maybe needed'to properly operate the ore is left on the screen, additional ore is added on top, through the hopper 10' and the cover 11 thereafter sealed. The process is then repeated. If preferred, the addition of ore and its treatment with acid may :be made quickly alternate, and so more'or less con tinuous, as is ordinarily the case where 9.

ji is used.

a vhile the jig form of dissolveris shown, anyothe'r form which will economically handle and properly agitate the material will do equally as well.

may be of considerable value. very many of the metal ions, hydrogen ions the chamber and communicating with the anode and cathode compartments respectively are two hoods, a and t, communicating respectively with gas-outlet pipes at and 'v.

To the chloride of iron in the tank k is added the necessary amount "of a proper liquid, for example, ammonium'oxalate, to form the electrolyte. The electrolyte is allowed to flow from the tank is through a pipe. w into the electrolyzer. When the liquid has reached the proper height, which will be well above the bottom of the partition 1" the supply is shut oh? by means of the valve m, and the current is turned on. The reaction will then be that chemically pure iron will attach itself'to the cathode q, while chlorine gas will be evolved at the anode together with some oxygen gas.

The chlorine gas evolved is carried oif through the pipe 24 to the tank 3 This tank contains-water which will dissolve part of the chlorine gas. If this be done in the presence of light, the chlorine water so 0 is the electrolytic chamber;

formed quickly changes to hydrochloric acid, and is-useful for the further leaching of ore. The excess chlorine is a by-product of sufiic'ient value to pay for the cost of what additional hydrochloric acid may be needed.

It may he mentioned, here, that in giving up'its iron, ferrous chloride consumes much less electric current than ferric chloride.

After the electrolyzer has done its work,

the cover of the hood 2? is opened 'or lifted off and the iron which has gathered on the cathode q is separated from the cathode and lifted out of the electrolyte, which is adapted for further use.

Any gas which is formed in the cathode compartment of the e-lectrolyzer is pulled off through the pipe 2;. Such gas may be drawn off into the same kind of apparatus as that shown (y) for the anode gas, and this apparatus mayor may not contain water dependent on the treatment, if any, to which the gas may be subjected. This cathode gas Thus, with are given "01f 'a'tthe cathode. Hydrogen, being a valuable by-product, should be saved, which can be done by the means described in this paragraph.

The next step in the process is the heating of the iron. At this stage the iron obtained is chemically pure and in that Condition is unfit for many industrial uses. It should be heated for the subsequent part of the process that properly prepares it for use. Any type of furnace will answer this purpose, but as chemically pure iron is quickly affected! by any gas, the electric furnace, which is more neutral in its heating than any other type, is preferable. If a gas heated furnace (for example, the open hearth) be used, special precautions will be necessary to save excessive waste of the iron by oxidation or other contamination.

If wrought iron is desired, the iron collected upon the cathode, which by now has, of course, been separated from the cathode, should have added to it any ingredient (for example, carbon) that is necessary to neutralize its tendency to oxidation, and should then be heated, preferably out of contact with air. It can be then put through the ordinary machinery of the well known rolling mill and rolled to the desired size as usual.

If steel is desired, the collected iron should be melted, also preferably in an electric furnace, and such ingredients as, for example, carbon, manganese, or, if an alloy be demanded, the necessary other metals, should be added to the bath or liquid material, either before or after the melting, according to well-known practice. The molten steel can then be cast in an ordinary mold if casting be desired, or in an ingot mold if it is desired to subsequently roll the steel.

Starting with chemically pure iron, it is! possible to secure a liquid steel or iron alloy of any analysis that may be desired and of great purity.

It is known that by electrolysis not only can one metal be picked out, but by a change of the potential of the current, and in some cases of the electrolyte other metals that may be present can also be separately obtained. For example, Oriskany iron ore, which is a limonite, contains appreciable quantities of zinc and of manganese, both of which can be won separately, from the iron and from each other, by following well known methods of electro-analysis.

Themanganese, for example, would be deposited on the anode, generally in the form of an oxide or peroxide. It is also possible to extract carbon on the iron, which is collected, by using the proper electrolyte and continuing the current after the iron is obtained. Carbon can thus be obtained on the iron fromthe oxalate electrolyte, and this may sometimes be advantageous in saving the iron from oxidation in the air and also'in preparing it for the making of steel.

From the foregoing description it will be noted that, in the use of the process to adapt it to the manufacture of iron or steel, the blast furnace is entirely eliminated, as is also the blooming-mill which is used in steel plants. The amount. of power needed to electrolyze the iron solution is only a part of that needed in the above two processes, and the amount of power used in the electric furnace has already demonstrated its economy as compared with heating bycoal or gangue, and separating the pure metal from the solution by electrolysis.

2. The process of extracting iron from its ores which comprises subjecting the ore to the action of a solvent of the metallic constituent, separating the solution from the gangue, adding an ingredient to the solution to form an electrolyte, and separating the metal from the solution by electrolysis.

3. The process of extracting iron from its ores which comprises subjecting the ore to the action of a solvent of the'metallic con stituent, separating the metal from the so lution by electrolysis, and separately removing from the electrolyzer the gases generated at the anode and cathode.

4. The process of extracting iron from its ores which comprises subjecting the ore .to the action of a solvent of the metallic constituent, separating the solutionfrom the gangue, separating the metal from the solution by electrolysis, and absorbing in water the gas generated at the anode.

5. The process of extracting iron from its ores which comprises subjecting the ore to the action of a solvent of the metallic constituent, separating the solution from the gangue, separating the metal from the solution by electrolysis, and collecting the gases generated in the electrolytic action.

6. The process of extracting iron from its ores which comprises subjecting the ore to the action of a solvent of the metallic constituent, separating the solution from the gangue, separating the metal from the solution by electrolysis, collecting the gases generated in the electrolytic action, and subjecting the metal collected at the cathode to a suitable heating operation to adapt it for ing the metal from the solution by electrolytic action, and separately removlng the gases evolved at the anode and cathode.

8. The process of treating ores containing iron in the form of an oxide for the purpose of extracting pure iron which comprises subjecting the ore to the action of an acid, separating the solution from the gangue, adding an ingredient to the solution to form an electrolyte, separating the metal from the solution by electrolytic action, separately removing from the electrolyzer the gases evolved at the anode and cathode, absorbing the gas evolved at the anode in Water, and subjecting the pure iron collected at the cathode to a suitable heating operation to prepare it for commercial use.

9. The process of extracting iron from its ores which comprises immersing the ore in a solvent of the metallic constituent, subjecting the ore and solvent to an agitating operation, separating the solution from the gangue, removing the gangue by agitation With Water, and separating the metal from the solution by electrolytic action.

10. The process of extracting metals from their ores which comprises immersing the ore in a solvent of the metallic constituent, subjecting the ore and solvent to an agitating operation, separating the solution from the gangue, Washing the gangue with Water, extracting the solvent from the washings, separating the metal from the solution by electrolytic action, and collecting the gases evolved in the electrolytic operation.

In testimony of Which invention, I have hereunto set my hand, at New York, N. Y., on this 26th day of October, 1918.

ARTHUR J. MOXHAM. 

